In a communications system, the communications system's capacity may be significantly improved when an enhanced NodeB (eNB), also commonly referred to as a NodeB, base station (BS), communications controller, transmitter, and the like, has full or partial knowledge of a channel over which it will be transmitting. Information related to the channel may be referred to as channel state information (CSI). CSI may be obtained by the eNB over a reverse feedback channel. A user equipment (UE), also commonly referred to as a mobile station (MS), terminal, subscriber, user, and the like, that receives transmissions made by the eNB may transmit CSI to the eNB over the reverse feedback channel.
In general, the UE may make measurements of a channel between the eNB and itself in order to determine the CSI. The eNB may transmit signals to help the UE make the measurements. The signals may be referred to as CSI Reference Signals or CSI-RS.